So I laid the blueberry and Capri together and the Capri is wider and has a longer rise. My DD has big legs and a short rise, so the blueberry cover doesn't fit her very well. The leg elastic left some red marks on her legs. Her legs usually require that we put her in 2T/3T pants, but her rise and her waist would actually probably fit a 12-18m size. I don't know If that explanation helps. After a day with the blueberry cover I definitely prefer the Capri for her body shape. Although, they're cut to fit over fitteds and prefolds, and I only put pad folded flats in them so they're still a little droopy. Not a perfect fit, but my DD is only 18mos and in 3T sizes there aren't much choices for covers. :-) So these are my fave for sure.
I'm not sure if that was even helpful. :-)